1. Field of the Invention
The present invention relates to avionics and hydraulics. More specifically, the present invention relates to systems and methods for inducing drag in missiles, torpedoes and other guided projectiles.
2. Description of the Related Art
It is often desirable to provide a fail-safe method for testing a missile or other vehicle on a range. Several methods have been employed to ensure fail-safe testing of a missile. One such method involves the use of explosives to detonate the missile. However, this approach is problematic inasmuch as it is risky and problematic to store explosives. In addition, the detonation of the missile can cause unacceptable collateral damage inasmuch as when a missile is detonated, it breaks into many pieces that result in a large debris field on the ground.
Another approach involves the use of hard over control surfaces. When activated, these surfaces steer the vehicle into the ground or other safe location. Unfortunately, the system for controlling the hard over control surfaces is typically the same system used to guide the missile. Failure of the guidance system can therefore also lead to a failure of a fail-safe system using this approach. Hence, for certain tests, an independent means of terminating a flight is preferred.
A third approach involves the use of drag doors. Drag doors are planar surfaces which are spring-loaded and attached to a missile body on one end and latched in a closed position on an opposite end thereof. When the latch is released, the door is deployed to an open position at which causes the vehicle to become unstable and crash within a predictable area on the ground. In this approach, the vehicle remains intact until impact with the ground. It is critical that the latch successfully actuates and releases the drag door.
Prior approaches for ensuring successful operation have included the use of electromagnets and solenoids. Electromagnets require electric power to hold the door in the closed position. Electromagnetics and solenoids are often too bulky and complex. The weight can adversely affect the performance of the missile and the complexity can limit reliability.
Hence, a need remains in the art for an improved system or method for effecting a latching of the drag door in a reliable manner.